For the Cookie Consent bar, if the user clicks the allow(OK) button, it should not be displayed again when any pages of this website is opened. If the cookie consent bar always showing on your WordPress website. And if there is an activated cache plugin on website, it should be an issue about that Cookie Consent bar conflicts with cache plugin.
On most of WordPress cache plugins, there are the options what are for excluding page, cache, and assets like CSS. They will not be cached.
WP Fastest Cache
If you use WP Fasted Cache plugin, please click WP Fastest Cache on the left menu bar of WordPress admin. You will enter the settings of the plugin. In Exclude tab, click Add New Rule after Exclude Cookies, the rule panel will popup. Enter cookieConsentBar and click save.
WP Optimize
If you use WP Optimize plugin, please go to WP-Optimize > Settings, click Cache, you will see the Cache settings panel. In Advanced settings tab, enter Enter cookieConsentBar in the List of cookies.
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